低温熔融盐体系电沉积制备铝锡合金

Preparation of aluminum-tin alloy by electrodeposition in low-temperature molten salt system

以AlCl_(3)-NaCl-KCl低温熔融盐体系作为电解质,无水SnCl_(2)作为原料,对电沉积制备Al-Sn合金进行研究。通过扫描电子显微镜(SEM)、能谱(EDS)和X射线衍射仪(XRD)分析合金产物的形貌和成分组成;通过极化曲线法和摩擦磨损实验对合金产物的耐蚀性和耐磨减摩性进行检测分析;通过维氏硬度计和涂层附着力自动划痕仪对合金产物的硬度与膜基结合力进行表征。结果表明:当SnCl_(2)添加量为0.04~0.08 g时可制备出锡含量为10%~18%的中锡铝合金,最佳沉积温度为160~200℃、沉积时间为40~50 min、电流密度为40~50 mA/cm^(2);随镀层中锡含量的提高,其耐蚀性逐渐变差,而耐摩擦磨损性能先提高后降低,并在SnCl_(2)添加量为0.06 g,即镀层中锡的含量为14 wt%时有最佳摩擦磨损性能;沉积温度对合金镀层的硬度及结合力有很大影响,随沉积温度的升高,合金镀层的膜基结合力和硬度均呈现先提高后降低的趋势,当沉积温度为200℃时,其结合力和硬度最佳。

AlCl3-NaCl-KCl low-temperature molten salt system with anhydrous SnCl2 was used to study the preparation of Al-Sn alloy by electrodeposition.The morphology and composition of the alloy were analyzed by scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS)and X-ray diffraction(XRD);The corrosion resistance,wear resistance and antifriction of the alloy were tested and analyzed respectively by polarization curve method and wear and friction experiment;The hardnesses of the alloy and the film substrate adhesion were characterized respectively by Vickers hardness tester and automatic scratch tester for coating adhesion.The results showed that when the SnCl2 content in the electrolyte was 0.04−0.08 g,a medium tin-aluminum alloy with tin content of 10%−18%could be prepared.The optimum deposition temperature was 160−200℃,the deposition time was 40−50 min,and the current density was 40−50 mA/cm2.With the increase of tin content in the coating,its corrosion resistance gradually became worse and the friction and wear resistance showed a trend of increasing first and then decreasing.When the SnCl2 content was 0.06 g,the tin content in the coating was 14 wt%,the friction and wear resistance were the best.With the increase of the deposition temperature,the film substrate adhesion and hardness of the alloy coating showed a trend of increasing first and then decreasing.When the deposition temperature was 200℃,the best adhesion and hardness were obtained.